Would legalizing illicit opioids reduce overdose fatalities? Implications from a natural experiment
NDARC’s Professors Michael Farrell and Shane Darke argue that the case for legalised heroin to reduce overdose deaths rests on the validity of two assumptions: that variations in purity and/or the presence of contaminants are the major causes of overdose. In fact most heroin related deaths are due to the combined effects of polydrug use, they argue. While tolerance is associated with substantially increased risk of death, particularly after a period of abstinence such as imprisonment or detoxification, the risk in such cases is so much higher that purity is less relevant.
The increased use of prescription opioids serves as a natural experiment to test the validity of the legalisation argument. The substantial rise in pharmaceutical opioid deaths around the world, and the United States in particular, show that opioids of known purity, and with no impurities, are killing increasing numbers of people.
The model addressed in the article is similar to alcohol where use is by the individual in a setting of their own choosing. A restricted model, where heroin is provided in a supervised treatment setting, is associated with substantially reduced mortality. But it is unlikely that such a model would be comprehensively introduced.
The authors conclude that legalisation of heroin is unlikely to result in major reductions in overdose deaths, as most deaths are not attributable to unstable purity or the presence of impurities.